Updated

HOBOKEN, N.J. -- A train from New York pulling into the station for its final stop crashed into the bumpers at the end of the tracks Sunday morning, injuring 34 people and shutting down service indefinitely.

None of the injuries in the 8:30 a.m. crash were considered life-threatening, though several victims were taken away on stretchers or put in neck braces as a precaution, Hoboken Mayor Dawn Zimmer said. The injured -- who mostly sustained cuts and bruises -- were taken to three area hospitals for treatment, and most, if not all, were expected to be released later in the day.

The cause of the crash remains under investigation, but city police said it appears that a mechanical failure is to blame. The National Transportation Safety Board and the Port Authority of New York and New Jersey are investigating.

Passengers on the train, which had departed earlier in the morning from New York City, said it had been a routine trip until they suddenly were knocked around by the impact.

"People were stunned, but nobody was really going crazy or anything," said Tom Gordon of Jersey City, who was riding in the train's front car with about 15 other people. "I didn't know what had happened at first."

Gordon, who was headed home from his job as a security person at a New York City apartment building, said he was half-asleep as the train pulled into the station on track No. 2. But he was quickly awakened and jolted from his seat by the crash.

He was taken to Hoboken University Medical Center for treatment of minor arm and rib injuries and left the hospital Sunday afternoon with his arm in a sling.

"I just want to get home," he said while waiting for his wife to pick him up.

Witnesses described the scene as the station as "controlled chaos," saying people were mostly calm but very concerned for the injured. Zimmer praised the efforts of emergency responders, both from Hoboken and surrounding communities who answered their call for assistance.

"Everyone did a great job," she said.

Allison Portney of Rockland County, N.Y., was walking just outside the station to catch a New Jersey Transit train home when she saw many people slowly emerging from the station. The last victim to be removed from the scene was taken away on a stretcher around 11:30 a.m.

"Most of (the injured) were walking, but they all looked pretty shaken," Portney said.

Zimmer said one of the two train tracks may be reopened Sunday afternoon. Officials hope the other will open in time for the Monday morning commute. Nevertheless, additional bus and ferry service will be provided.

Zimmer said updated information on service disruptions would be posted on the city's and Port Authority's websites.